Irrevocable promises: Finance leases.

(b) A promise that has become irrevocable and independent under subsection (a) of this section: (1) Is effective and enforceable between the parties and by or against third parties including assignees of the parties; and (2) Is not subject to cancellation, termination, modification, repudiation, excuse or substitution without the consent of the party to which the promise runs. (c) This section does not affect the validity under any other law of a covenant in any lease agreement making the lessee's promises irrevocable and independent upon the lessee's acceptance of the goods.